Detonator for ordnance-projectiles.



C. P. WATSON.

DETONATOR FOR ORDNANCE .PROJECTILES.

APPLICATION HLED NOV. 21, 1914.

1,1 QZM 4. Patent-ed Sept. 5, 1916.

C. P. WATSON.

DETONATOR FOR ORDNANCE PROJECTILES.

APPLICATION FILED NOV. 21, I914.

PatntedSept. 5, 1916.

"Z SHEETS SHEET 2.

1; Figs. 3

the line llllll of Fig. 1' 'lmt Cl-IAELES 3?. 1 V ATSOII, 0F IP'HXLADELPl-EIA, PENNSYLVANIA, ASSIGHOR 130 THE "WATSON 413313155 GOB'IPANY, A COBPORATXON 03? DELAWABE.

'DETGR'ATQR TEGR ANCE-PIROJECTILE$ Specification of Letters Patent.

.elpplieation filed November 21 1914.. Serial No. 873,280.

Fitate of Pennsylvania, have invented certain new and useful Improvements in Detonators for Ordnance-Projectiles, which the following is a specification.

My invention relaihes to dctonator for ordnance pr.

It has been devised with especial referonce to use in connection with projectiles loaded with high explosives and has for its object to render the detonator certain in itsoperation and also absolutely safe, that is to say, it is of such construction and arrangement that it cannot possibly be armed except by the firing of the shell from the gun, and at the same time it will positively :TllfiV-"Ellfi the c DlOSlVQ charge Within the shell from being ignited or detonated should, through any unforeseen circumstance, the prim ng charge or" the detonator or any part thereof detonate or explode. These objects are successfully attained by the use or" my invention.

in the accompanying drawings 1 have illustrated the preferred form of such in rention, Without however Wishing by such delineation to restrict myself to the arrangement and detail shown, as that may be modified or changed Without departing from the principle of the invention.

ln such drawings, Figure 1 is a central lo itud'. section or" a detonatorembcdy in my invention; is a/transrerse clonal View talren on the line ll-ll of and i are sectional views both taken on V viewed respectively from difi'erentdirections. Fig. 5 is a detail View in elevation of the plunger that carries the firing pin, and the associated parts that operate it, such pin being represented in the armed or firing position; Fig. 6 is a longitudinal scctionalviow of the parts represented in 1y. the posl on they there occupy. dial" to (3 except that :escnted as in n l L113 on: r

s 3". l on one we e c .1." .L 1 sectional accept rnactne parts are represented in the normal inactive position represented in Fig. '4'. Fig. 10 is a detail View in perspective illustrating one of the centrifugally-acting bodies employed to control the positions of the firing pin; Fig. 11 is a detail longitudinal sectional View of the support for the primer, the miniature projectile that contains a detonating charge of high explosive and the charge of powder that props 5 said miniature pro tile; Fig. 12 is a View in central longitudinal section showing one Way of mounting the firing pin for the miniature projectile the dctonating charge of sensitive explosive different from that shown in Fig. 1. Fig. 13 is a transverse section taken on the line XHIXHI of Fig. l.

In the drawings 2 indicates the body of the detbnator. It is preferably in the form of a steel plug of high tensile strength adapted to be screwed into the breech of a shell, and bored out to form a central chamber open at its forward end. The rear portion of this chamber is smooth and. contains a ponderous body, in the form of a plunger 3, that fits this part of the chamber quite closely and is free to more therein longitudinally to a limited extent.

5 indicates a spring interposed between the rear end of the plunger and the body of the detonator and acting to normally hold the plunger in its forwardmost position. While this spring is not essential to my in- Vention I prefer to use it, as it holds the plunger quite firmly in the position 'cpicsented in Fig. 1, and prevents it from mo ing as the shell is being handled, and though such movement would be attendcd'rliih no danger it might awakensuspicion on die part of one handling a shell equipped with my loosely mounted the stem of the firing pin vThis pin has a head 8 with inclined .eral edges, and with a shallow e ta er cts beyond me thereof proje (if, of the plunger 3, and Wl.

lies the body of the pi.

and the carrying retract d such point head 8 extends well within the transverse opening A coiled spring 9 surrounds the stem of the firing pin and is located between its head and the body of the plunger, and operates to retract the pin so that its point or firing end is entirely within the aperture (1 and back of the front face of the ')lungc'r.

Fitting within the transverse openinglst in the plunger a re two centrifugally acting, counterpart, bodies 11, 11., each provided with a locl'i'ng and wedge member 12. Each. .vedge member 12' is relatively thin, and the two are adapted to overlap and lie alongside of each other face to face bodies 11 are moved inward as indicated in Figs. '4' and S), and to slide over each other as the said bodies move outward to the posi tions indicated in (i and Each. member 12 is formed with a locking-shoulde 13 that is adapted to overlie the head of the firing pin and hold it retracted when the parts are in inactive, normal position, Figs. 7 and 9; and also with an inclined wedge part 1* that engages with the inclined edge of the head of the pin and, in coiiperation with its like companion member, operates to force the firing pin outward into armed position, when the bodies 11 are thrown outward by centrifugal force. is has been stated, the sprin tends to move the firing pin inward into the body of the plunger, and such spring hence operates, through the engagement of the inclined faces of the head of the pin with the inclined edges of the wedge portions 14: of the centrifugally operating members 11, to move the latter inward to a central position, with he flat base parts 15 said bodies directly back of and in engagement with the inner face of the firing pin head.

It is conceivable that a loaded shell might be subjected to a force that would tend to move one of the bodies ll. outward, for instance should it fall upon its side; but this would not arm the detonator, for the reason that the locking shoulder 13 of the opposite body 11 would prevent the outward movement of the pin. It requires the simultaneous and conjoint MK-i011 of the two wedge parts H, acting upon the head of the firing pin, to move it forward, against the action of the spring 9, and into armed position,

and this can only take place when the detonator is subjected to rapid rotation. This latter occurs only, after the detonator has been applied to a. shell, when the shell is fired from a gun, and hence no circumstances incident to the ordinary handling of the shell, or any accidents to which it might be subjected can possibly arm the firingpin of the detonator. WVhen, however, the shell is fired and begins to rotate, the two bodies 11 simultaneously. move outward and separate the wedge faces ll. which act upon the head of the firing pin from opposite sides and when the project forward, against the force of the spring 9; and at the same time the shoulders 13.are withdrawn from over the head 8 leaving the firing pin free to be moved forward. By the time the bodies 11 reach the limits of their. outward movements their faces come intoengagement with the inner wall of the detonator body by which they are arres'et, when the ends of the wedge parts are brought together under the center of the head of the firing pin and enter the recess 10 formed therein, the spring setting back the firing pin to cause this. llhe edges of the recess, and the ends of the wedges 14, are so shaped that when they come together as just mentioned the head of the firing pin ,forms a. lock that holds the bodies 11 out ward the spring 9 insuring constant engagementbetween said locking parts. This is desirable for two reasons: The parts 14 of the centrifugally acting bodies constitute a solid abutment behind the firing pin and between it and the heavy plunger 3 as soon as the pin comes into armed. position and the lock aforesaid insures that this solid abutment shall be maintained even though centrifugal force should be largely reduced by the slowing down of the speed of rota.- tion of the shell during its flight.

-32, 112 indicate small. pins or studs extend ing from the outer faces of the bodies 11 and adapted to enter a circuu'iferential recess formed in the inner wall of the detonator body when the plunger has been fully set back. This set back of the plui'iger takes place, as is well understood, when the gun is discharged. The pins operate to posi tively hold the plunger from creeping forward after acceleration in the flight of the shell has ceased. They are of such size that they are sheared off at the moment of impact of the shell, then allowing the plunger to move forward relative to the detonator body, the spring assisting in causing such forward movement. They may be formed integral with the bodies 11, or of lead or some other soft material secured to such bodies. These pins serve not only to hold the plunger in its set back position as has been described, but, if properly proportioned in length to the other parts of the apparatus with which they are associated, they may also serve to prevent the bodies 11, 1 either of them, from being moved outward.sufliciently far to unlock the firing pin except when the plunger is set back, thus adding another element of safety to the device, since the conjoint setting back of'the plunger and outward move ments of the centrifugally acting bodies 11 can take place only under condition. set up when the'shell is fired from a gun.

The shear pins 42 constitute means that are brought into operation during the light of the shell for positively holding the plunger in a fixed position with reference to the primer 1? until impact with the objective of the shell takes place. This has been found an important feature, since it tends to fix the duration of one of the time elements that enter'into the delay in detonation after im pact; for by positively fixing the position the plunger shall occupy with reference to the primer at the moment of impact, the disance the pliuiger has-to travel before t primer is engaged and fired is positively determined, and this distance may be greater or less, Within the limits of movementof the plunger, accordingly as a quicker or more delayed firing of the primer after impact may desired. Where means for thus fixthe position to be occupied by the plunger upon impact are not provided, the position of the latter becomes uncertain factor, it sometimes being close to the primer and somccimes farther from it, and l nence an element of uncertainty is introd ceil, thus making more diflicult to dcte nine the moment of detonation of the projectile than whenusing an arrangement such as 1 show and have just described.

Since chamber in W iich it mounted quite closely l find it desirable to form longitudinal air channels in it in order to permitair to circulate as it moves from one end of its travel to the other. "lhe air passages may be grooves 50 in the surface of the plunger, or longitudinal perfora ions through the body of the plunger.

There is supported Within the body of detonator and directly in front of plunger 3 a plug or supportin which is mounted the primer and the detonating capsule or miniature projectile containing. small charge of high explosive. The support, represented in detail in F '11, is designated 16 and is preferably screwed into the body 2 as indicated in Fig. 1. It is provided with a seat for the cap or primer 17 and with a chamber 18, communicating the the through a small hole or flash passage 19' with the recessin which is seated the cap 17. in the rear portion of this chamber is placed a charge of black powder, indicated at lfl, and directly in front of this is sale or miniature shell 20 containinga high explosive, such as'fulminatc of mercury. A wad 21 preferably separates the charge of blaclc powder from the base of the capsule 20. The latter is preferably formed of a. steel shell with a remo'able head 22 secured to and closing the front open end thereof, through which the shell is charged. This head is perforated and formed with a seat for a detonatiug cap 23.

The booster charge.

dcionalion 44,..1

the the dclonator am a of thcshell, located n i of the chamber at the rorwari a Lu-e dciional'or bodv The booster stance.

' ieclosed by a valve device plug 16.

the plunger fits the Walls of the.

in line with the corrugated tube 37-through Which the pro- ]ectxlo or capsule a capcharge should be of an explosive material that is relatively highly resistant to shock and heat, and tri-nitrotoluol is such a sub- This chamber 2%: is separated from the rest of the detonator chamber by a plug 25, screwed into the body .2, and centrally perforated, at 26, in line with the capsule 21). The inner end of the passage 26 1s 27. I prefer that be formed as a projection careful ground to fit itsseat at the end of passa e 26, and carried by or formed iiitegral with a plate 28 pivoted to the forward face of a. sliding valve carrier This latter is perforated at30, also in line with the capsule and the perforation 26. it is normally held in a. forward position with the valve 27 seated, by a coiled spring 81 interposed between the valve carrier and the The latter is preferably formed with a fmrwardly projecting reduced portion 32 around which the spring 31 is coiled and constituting the seat for the capsuleQO. The valve and its supporting plate are eccentrically pivoted at to tho outer face of the valve carrier, and are acted upon by a spring 34- that normally holds the plate against a stop pin with the valve in position to close t is passage 26.

36 indicates a shallow seat formed in the inner face of the plug concentric with the opening 28, into which the face of the 27 sets when thrown outward by contrifugal force to uncover the opening 26, as will be described.

38 is a. plate screwed into the inner open end of the detonator body and closing the chamber 2% that incloses the detonating booster charge. It carries a firing pin 39 that is directly in front of'and in line with the capsule or small projectile 20, and is arranged to act through the central perform tion in the head thereof upon the cap 23. Between the plug 25 and the plate 38, and openings 26 and is a this valve shall 20 passes in its flight toward its firing pin 39. This tube is hermetically sealed at its ends in the supports in which it is mounted and serves to separate lhe passage for the capsule 20 from the charge of explosive within the chamber 24, and, being corrugated, forms air passages for renting the tube as the said projectile enters and passes through it.

Instead of supporting the pin 39 that fires the charge of the miniature projectile 2O rigidly as has been described, it may be loosely mounted Within the corrugated tube 37 and supported upon a sprii'lg 51, interposed between. the base of the pin and the plate 38, as reprcscn'cd in Fig. /i ith this arrangement the ring 51 holds the firing pin normal. :ear the inner end of the tube 3?.

But upon impact of .he I

shell the pin jumps forward, compressing the spring Upon slight impact, as when striking thih armor, the distance that this firing pin moves forward and the amount 1t compresses the spring will be less than the distance it moves when the impact is more severe, as when heavy armor is struck, and this feature of operation may be utilized to automatically govern the time of exploding the shell after impact; for, will be seen, the firing pin less distant from the seat of the miniature projectile when light armor is struck, than it is when heavy armor is encountered, and l. the said miniature projectile has to travel a. greater distance before it is detonated in the latter case than in the former. The time it takes in traveling this greater distance can be made to correspond with the difference between the time taken by the shell to penetrate light armor and heavy armor. The same result as that just described may be accomplished by means of an air spring in place of the metallic spring 51 illustrated in the drawings.

40 indicates a pointed pin of hard tool and projecting rearward.

The supporting plug 16 is provided with one or more longitudinal through passages 41.

\Vith this description oi? the detail construction the detonator, a general state ment of its advantages and. method of operation may so given. Fig. 1 represents the device with its parts in normal position, that is, unarmed. It will be seen that the firing pin 7 is retracted so that it cannot possibly be brought into engagement with the cap 17 and that no manipulation of the shell nor any movement thereoi except such movements as are imparted to it in the act of being fired from a gun can possibly arm the detonator and set the firing pin in position to act upon the said cap. It will also be seen that the passage between the chamher in which is situated the plug 16 and where are located the detxmatirn capsule 20,

the charge of powder 15) that propels it, and

the primer caps 17 and 23,--all explosives booster charge. which is not sensitive to shock or heat. by a gas-tight valve, so that should the said sensitive explosives, or any of them, through any ause whatever detonate or explode, the name and gases and incident detonating waves. from them cannot possibly reach the chamber 2 containing the booster charge of high explosive. It will also be observed that the passages 41 through the plug 16 permit the gases which would be generated by a premature detonation oi the charge of the capsule 20 to pass to the rear of the said plug, as well as to fill the ohan'iber directly in front thereof,

held during the flight of the shell. t c;

so that the pressure of these cases is instantly very much reduced through c: pansion, as well as by being robbed of their heat by the surrounding metal. The great pressure that would be exerted in the chamher in which is located the plug '16 by such premature explosion would operate to press forward the valve carrierQS), and force the valve more tightly into its seat, thus 1ncreasing its etlcctiveness in preventing the passage of any of the said gases beyond said valve and into the tube 37. If there should be some slight passage of gas beyond. the valve it would do no harm, since the tube 37 would prevent its direct action upon the charge within the chamber 24-, the tube being, as stated. hermetically sealed at each end in its supports.

Upon a shell carrying a dctonator such as that described beingfircd from a gun the plunger 3 is violently set back, compressing the spring 4- and forcing the hard steel point 40 into the softer metal oi the body. The plunger will move back until the pins 4-2 carried. by the centrifugally-operating bodies 11 come opposite to the groove 4-3 formed in the detonator body. At the same time the valve carrier or plunger 29 moves towa l thc rear, compressing the spring 31 and freeing the valve 27 fronr its seat. The rotary motion given to the shell by the riiiing oi the gun is positivelfvf communicated to the plunger 3 by reason" of the pin {4.0 being embedded somewhat in the body of the detonator; while rotation is in'iparted to the valve carrier 29 because of the frietional engagement .ithas with .the inner walls of the'detonator body and the comprcssion of the spring 31. The centrifugal force generated by rota tion of the shell acts to simultaneously move outward the two bodies 11, forcing forward and into armed position the firing pin 7 where it is locked in the manner already described. As the bodies reach me limits of their outward movemen the pins 42 which they carry enter the recesses 43, and the plunger is thus locked in its rearmost position. where it ,1 1 ugal force also acting upon the valve .57 causes it to swing from the position indicated in full lines in Fig. 4, to that indicated in dotted lines, when, it will be seen, the Spring 34 lies nearly across the pivot 33-,

and hence exerts very little force lending to restore the valve to its central position.

,ha' soon as the accclcrathm of the shell has ceased the spring 31 moves the valve carrier forward until the face oi the valve comes into engagement with the groom in the inner faceof the plug where it will he come seated and be held, by centrifugal force and the spring 31, out of the line o of the detonating capsule or projectile 20,1n front 0t which is now a free pask oil the pins 42 which have old it retracted, and the firing 11 ii then pin strihes the cap 17, exploding it. This ignites the charge of black powder 19 which operates to propel the small projectile 20 carrying the detoiiating charge forward ough the perforations 30, and 26 and the e 37. Upon reaching the firing pin 39, cap 23 is exploded, the detonation of the Within the capsule 20 takes place, and this in turn detonates the booster the chamber 24-, rupturing the deand the charge Within the ill he seen that the firing of tie shell stepping-up process accomplished cc ssion of explosions or minor detothat although these successive sions follow one another rapidly, an length of time occurs between :he shell and the final detonation actio First, upon impact, the plunger has io travel forward until the firing pin. acts oon the cap or primer 1?, then this has to the char 'e of powder 19 that propels the capsule or shell containing the detonatbarge, this has to travel from the posilion it norn'ially occupies to the end of the tuhe 37, and then be exploded, and finally the ecls olits explosion have to lie COX'fliuunioited to and detonate the booster. charge and this in turn rupture the deto nator and set oil the charge Within the shell. iis retarding of the detonation of the shell to accurately determine the of tiz'uc after impact when. the shell nu-st, because by varying the amount siox'rder charge, 19, the speed at which 'ature projectile moves toward the may he governed and hence line after impact when the 1e capsule shall be fired. understood thatthe capsule lite ch 3r quite snugly he that the .2 shell even when piercing ,1 armor will not dislodge it. its propul caused entirely by the charge of 'iat llie flight oi' the projectile red PlUYHlG the fus with a d in its rear end. For this puriorui a chuiuhe" ll in the rear end the detonator body into which is pac ed the tracer coiupouiul. This compressed 2c minim-1' at a comparatively low pressure. ius mulling unnecessarythe use .1 expensive high power compressing machiuery. The outer end of the chamber 4% tightly closed by a plate 45. This plate perforated at 46, and such perforation is Med with l'usihle metal. Between the plate a and the charge 7 of tracer compound is charge 48 of hlaclr powder. Upon. the gun being fired the tremendous pressure exerted Within the gun forces forward the plate compressing the charge i to a degree not practicahleby the us of any inachinery of which I have knowledge. This compression takes place practically instantaneously, and immediately thereafter the 'loination or a detonetor body, a longitudinally movable firing pin, a support "Within the said body in which the firing pin is mounted, and into the body of which the pin may he longitudinally retracted, and means for projecting the pin longitudinally on right lines, and beyond the face of the hody in which it is supported when said means are acted 'upon by centrifugal force.

2. In a detonator for projectiles, the combination of a detonator body, a plunger slidable therein, a longitudinally movable firing pin carried by the plunger and arranged to be retracted into the body thereof, and means for projecting the firin pin beyond the surface of the plunger when acted upon by centrifugal force.

In a detonator for projectiles, the combination of a detonatorfbody a plunger slidahle therein, a longitudinally .inovable firing pin carried by the plunger and arranged to be retracted into the body thereof, andcentrifugally operated de ices arranged within. the said plunger and acting upon the firing pin for projecting it longitudinally beyond the sin-face of the plunger when acted upon by centrifugal force. I

l In a detonator for projectiles, lhe C0111" liiuation of detonator body, a longitudinally movable firing pin, a support ithin the said body in which firing pin i mounted, and into the body of which the may he longitudinally retracted, and means for projecting the pin. longitiuluially and beyond the face oi the body in which it is supported when acted upon by centrifugal force,'the said means being constructed also to iocl: the pin retracted under normal conditions.

5. in a detonator for rojectiles, the com hination oi detonator ody, a firing pin, a support Within the said body in which the firing pin is mounted and into the body or which the pin may he longitudinally reiii-acted, and a plurality of radially sliding devices acting upon the said pin for proion Cli

the body in which 1t is supported when act-ed LlW/Al ecting it longitudinally beyond the face of upon by centrifugal force, each of the said devices being arranged to lock the pin retracted when in normal position but release it when moved by centrifugal force, whereby simultaneous movement of all the said devices is necessary to release the firing pin.

In a detonator for projectiles, the coinhination of a, detonator body, a firing pin, a support within the body in which the said pin ismounted and into the body of which it may he longitudinally retracted, a spring tending to move the pin within the said body in support, and means for projecting the pin longitudinally and against the action of the said spring into armed position when such means are acted upon by centrifugal force.

7. in a detonator for projectiles, the comlination of a (letonator body, a, plunger slidahle therein, in which is formed a transverse opening and also a central longitudh nal perforation, a longitudinally sliding liriug pin sealed in the said perforation, radially slioing bodies mounted in the said transverse opening arranger-l to act upon the said pin and project it into armed position when they are acted upon by ccntrifi force.

8. In a :letonator for projectiles, the combination of a detonator body. a plui'sgcr slid-- able therein, in whicn is formed a transverse og iening and a central longitudinal perforation, a longitudinall movable firing pin seated inthe said perforation, radiall slidbodies mounted in the said tran verse opening arranged to act upon the said pin and project it into armed position when they ar acted upon by centrifugal force, each of the said bodics being provided with means for locking the pin in retracted position under normal conditions. I

ll. The combination in a percussion fuse ol an anvil block and a hammer block movable the one with respect to the other longitudh nally oi the structure, a firing pin movable longitiulinally in the said hamn'icr block from an unarmed to armed position. and ccntri'l'ugally operated means for shifting said firing pin from unarmed position toward said anvil.

ill. The combination in a percussion fuse ol a supporting body, a firing-pin movable in said body from an unarmed to armed position, and a pair of oppositely arranged centrifugally-operating slidcs each provided with. an inclined face and with a transverse liring-pin-supporting surface,

ll. In a. detonator for ordnance shells coutaining av booster charge of high cxplosivc, a miniature projectile containing a detonatiug chargc l'or iirin the booslci charge. normally supported within the dctonator at uriug-pin-impclling surdistance from the booster charge, a charge of powder for propelling the miniature projectile into proximity to the booster charge,

means operating upon impact of the shell for igniting the said powder charge, means for detonating the said miniature projectile upon the termination of its flight and in proximity to thebooster charge, and a valve for clos gas-tight and against, the flightof the said miniature projectile the Cllfilll'b her in which is located the said miniature projectile the valve being arranged to open the pas ige upon the firing of the shell from a piece of ordnance In a detonator for ordnance shells, a dctonator body formed with two chambers in one of which is located a booster charge of cx ilosive, and in the other of which, at a distance from the first mentioned chamber, normally supported a miniature projectile carrying a detonating; charge for setting oil the booster charge, strongjpartition separating the chambers in which the said charges are respectively normally located, ther being a communicating passage between the chambers throu h the said parti-- a tion, a in,

ve closing said passage gas-tight, means for causing the valve to open upon the dim-barge of the shell from the gun, a charge oi powder for propelling the miniatum projcitile from its normal position, through the said p sage, into the chamber tainiug the booster cuargc and means optin upon impact of the shell for igniting id powder charge to cause it to pro jcct the miniature projectile with its detonalin charge into proximity to the booster char and there causing it to detonate.

13. in a dctonator ,t'or ordnance shells, a dctonator body having a chamber for a boosicr charge and another chamher for a charge of an explosive of sensitive charac' tcr 'l'or igniting the booster charge, and a stinugparlilion separating the said chambers throire h which is a communicating passage uniting the chambers, a valve for closiug the said passage gas-tight, a movable sliding carrier for the valve arranged to be set back and free the valve upon the shell being iired from the gun. the valve being arrangcd to be moved by centrifugal force out ol position to close the said passage, and. menus l or tiring the said charges upon impact of the shell. I

1-1. in a dctonuto-r. a ase or body having a handler for a boosl'cl charge ol non-sensilivc high explosive and another chamber remote thcrcfrom containing a detonating charge of sensitive explosive 'l'or dctouatiug the booslcr charge, the said chaiu crs being .lnator is applied is fired from a gun, and a sliding carrier for the valve located in that chamber in which is the sensitive detonating charge movable in the detonator body and. ormally held in position to seat the valve, whereby should the sensitive explosive accidentally explode v or detonate,= the pressr of gases causedthereby will act upon me said valve carrier and more tightly in rearbf the said plug carrying a firing pin, and means for arming the firing pin by centrifugal action at the instant the shell is fired from the gun.

16. In a detonator for ordnance shells, a detonatorbody inclosing a chamber for a booster charge and another chamber separated therefrom by a strong partition through which is a passage uniting the said chambers, a'plug secured in the second chamber adapted to support a miniature projectile containing a sensitive high explosive, a charge of powder for propelling the said miniature projectile from its seat through.

the said passage into the chamber of the booster charge and a primer for igniting the said powder charge, a plunger in rear of the said plug carrying a firing pin, means for arming the firing pin by centrifugal action at the instant the shellis fired from the gun, and a valve for normally closing the passage between the said chambers gas-tight arranged to be moved to uncover the said passage when the shell is fired from a gun, the said plug'having formed in it longitudimilly through perforations whereby the parts of the chamber in which it is situated on opposite sides of the plug are in communication to permit expansion of v the gases should there be a premature explosion or detonation of the sensitive explosive in such chamber.

17. in a detonator for ordnance shells, a dctonator body having, a chamber for a booster charge of high explosive near its front end, a strong partition cutting oll' said chamber from the interior of the rest of the body, such partition being centrally perforated, a chan'ibcrcd plug seated in the chamher in rear or me said partition having a forwardly extending part of reduced diameter, a miniature projectile carrying a sensitive detonating charge seated in the reduced part of the said plug, a charge of powder for propelling the said projectile located in 1' ar of said miniature projectile, a valve for clos ing gas-tight the passage through the aforesaid partition, "the va lve being arrangedrto move to uncover the passage when the shell is fired, a m vable valve carrierbetween the'.

said plug and partition fitting tightly within the detonator body, a spring surrounding thereduced portion of the plug and actin upon the movable valve carrier to normally hold the valve to .its seat, and a plunger carrying a firing'pin located in rear of the said plug arranged upon impact of the shell to ignite the charge of powder that propels the miniature projectile, and means for causing detonation, of the said miniature projectile when it arrives in proximity to the booster charge.

18. In a detonator for ordnance projec tiles, :1 plunger carrying a firing pin and adapted to be set back when the projectile is discharged, bodies seated in thesaid plunger movable outward from the axis of the dctonator under the influence of centrifugal force due to the rotation of the projectile,

the said bodies carrying pins to engage with the walls of the detonator and hold the plun-v ger retracted, the said pins being easily frangible whereby they are sheared upon impact of lhe projectile.

15). In a detonator for ordnance projeotiles, a plunger operative in firing the primer of the detonator adapted to be set bacl; when the pro ectlle 1S discharged, and means,ar-

ranged to be brought into operation by centrifugal force due to the rotation of the pro jectilc in flight for positively holding the plunger in a fixed set-back position with refercnce to its forward limit of movement the said means being frangible and arranged to be sheared or broken upon impact of the projectile.

20. In a dctonator for ordnance projectiles, a plunger ofwrative in firing the primer of the detonator, and means arranged to be brought into operation by centrifugal force due to the rotation of the projectile in flight for positively holding the plunger in a fixed position back of its forward limit of move-- ment, the said meansbeing frangible and arranged to be broken upon impact of the projectile. p p

'( l lA It LES l. \VATSON.

lVitncsscs:

How/um vl. LEWIS,

(loco. l5. linira'rnlcu. 

